new 2009 Tahoe LTZ owner

[OR VietVet]

Reading thru this, I think the oil pressure higher request, is for peace of mind. My vote is on the pickup tube o-ring. I really like to look down and see at idle 40+ psi on my gauge.

 

[stretchb1953]

just checked the Tahoe after a day of driving. P0521 code is back, so apparently 20PSI to 25PSI is not enough pressure to keep light off. also it only climbs to about 30PSI at 60 MPH. i'm thinking about trying some 10W-30 oil to see if pressure increases. if it doesn't help keep that CEL off, then guess i'm going to have to bite the bullet for a new oil pump and pickup screen. would do it myself, but i don't have a decent place to work on it. i do all my maintenance in my driveway.

well did some checking with the local mechanic shops.. most of them quoted $400.00 to $500.00 to replace the o ring on the pick up tube. guess i'm gonna have to bite the bullet and overcome my phobia of crawling under anything heavy. back ground, i was crushed by a helicopter back in 2007 and don't like crawling under anything other than a kitchen sink. lol.

 

[stretchb1953]

Reading thru this, I think the oil pressure higher request, is for peace of mind. My vote is on the pickup tube o-ring. I really like to look down and see at idle 40+ psi on my gauge.

everything I have ever driven has had an oil pressure of at least 40PSI.

 

[OR VietVet]

well did some checking with the local mechanic shops.. most of them quoted $400.00 to $500.00 to replace the o ring on the pick up tube. guess i'm gonna have to bite the bullet and overcome my phobia of crawling under anything heavy. back ground, i was crushed by a helicopter back in 2007 and don't like crawling under anything other than a kitchen sink. lol.

I recently had a scare when my girl was in my Z71 and doing as I asked, power braking short bursts. I was under the rear axle area and was up on drive on ramps. Both the ramps shifted at same time and almost spit out the back and that would have brought the rear diff down on my waist. Was a little scary. She is now freaked whenever I crawl under the vehicles I work on. In you case, when you do this the engine will not be running. I now use two sets of ramps and elevate the whole vehicle and is then level. I have never been a fan of jack stands, even though I worked with them for over 40 years. IMO, drive yours up on 4 ramps and set the park brake. You can also do as I do. I have the rubber wedge wheel blocks. You can kick those in and set those while up on the ramps.

 

[j91z28d1]

just checked the Tahoe after a day of driving. P0521 code is back, so apparently 20PSI to 25PSI is not enough pressure to keep light off. also it only climbs to about 30PSI at 60 MPH. i'm thinking about trying some 10W-30 oil to see if pressure increases. if it doesn't help keep that CEL off, then guess i'm going to have to bite the bullet for a new oil pump and pickup screen. would do it myself, but i don't have a decent place to work on it. i do all my maintenance in my driveway.

I'm out of the loop, haven't been following along. but are you saying you're throwing a code for low oil pressure with 20psi at idle?

so the book(shop software really) I have access to is very specific about oil pressure. there's 3 different codes just for different oil pressure related stuff. P0521 says oil pressure sensor performance. not low oil pressure, it is different.


minimum hot spec.
6 psi at 1000rpm
18psi at 2000rpm
24 psi at 4000rpm

condition for P0521 being set... the ecm detects that the difference between predicted oil pressure and actual oil pressure is either less than 6.8psi or greater than 7.3psi.


circuit/system verification:
engine ON, observe the engine oil pressure sensor parameter. The reading should be between 6-65psi.

circuit/system testing:
1. engine On, transmission in park. vary the engine speed by 500rpm.
2. verify the scan tool engine oil pressure sensor parameter changes by more than 5psi. (if less than 5psi refer to oil pressure diagnosis and testing.
3. if the pressure test normal replace engine oil pressure sensor.

the oil pressure testing links to removing your oil filter and installing a mechanical gauge and looking for the min pressures above. the 6psi at 1000rpm stuff.

from the tests I've seen people do, it's always higher at the filter location than the back of the block sensor location with the same mechanical gauge anyways. but book says test with screw on oil filter adapter.


I honestly hate to see you dropping front diff, oil pan and pumps over something honestly a non issues. I've noticed a trend of everyone thinking everyone has a bad o ring, it rarely seems to be the fix all, and then you gotta go back in a 2nd time to install a high volume oil pump to get the needle up where you think it should be. when really an ls will out live all of us on 10psi hot idle oil pressure.


just my 2 cents.

 

[j91z28d1]

I recently had a scare when my girl was in my Z71 and doing as I asked, power braking short bursts. I was under the rear axle area and was up on drive on ramps. Both the ramps shifted at same time and almost spit out the back and that would have brought the rear diff down on my waist. Was a little scary. She is now freaked whenever I crawl under the vehicles I work on. In you case, when you do this the engine will not be running. I now use two sets of ramps and elevate the whole vehicle and is then level. I have never been a fan of jack stands, even though I worked with them for over 40 years. IMO, drive yours up on 4 ramps and set the park brake. You can also do as I do. I have the rubber wedge wheel blocks. You can kick those in and set those while up on the ramps.

that's proper scary.

you must have better ramps than I've been around. I've seen some flimsy looking things.

 

[OR VietVet]

that's proper scary.

you must have better ramps than I've been around. I've seen some flimsy looking things.

I have some Rhino Ramps.

https://www.amazon.com/RhinoGear-11912-RhinoRamps-Vehicle-Ramps/dp/B0117EESNC/ref=sr_1_2?crid=3AVMX2OA44HZ6&keywords=rhino%2Bramps&qid=1707283051&sprefix=rhino%2B%2Caps%2C162&sr=8-2&ufe=app_do%3Aamzn1.fos.18630bbb-fcbb-42f8-9767-857e17e03685&th=1

 

[j91z28d1]

I have some Rhino Ramps.

https://www.amazon.com/RhinoGear-11912-RhinoRamps-Vehicle-Ramps/dp/B0117EESNC/ref=sr_1_2?crid=3AVMX2OA44HZ6&keywords=rhino%2Bramps&qid=1707283051&sprefix=rhino%2B%2Caps%2C162&sr=8-2&ufe=app_do%3Aamzn1.fos.18630bbb-fcbb-42f8-9767-857e17e03685&th=1

ahh. I've only ever used the only thing tin metal ones. they seems iffy at best.

 

[OR VietVet]

The metal ones can be shorter on the ramp angle and cause drive on problems. I have a set but only use them for trucks. They also can slide on smooth concrete.

 

[stretchb1953]

I'm out of the loop, haven't been following along. but are you saying you're throwing a code for low oil pressure with 20psi at idle?

so the book(shop software really) I have access to is very specific about oil pressure. there's 3 different codes just for different oil pressure related stuff. P0521 says oil pressure sensor performance. not low oil pressure, it is different.


minimum hot spec.
6 psi at 1000rpm
18psi at 2000rpm
24 psi at 4000rpm

condition for P0521 being set... the ecm detects that the difference between predicted oil pressure and actual oil pressure is either less than 6.8psi or greater than 7.3psi.


circuit/system verification:
engine ON, observe the engine oil pressure sensor parameter. The reading should be between 6-65psi.

circuit/system testing:
1. engine On, transmission in park. vary the engine speed by 500rpm.
2. verify the scan tool engine oil pressure sensor parameter changes by more than 5psi. (if less than 5psi refer to oil pressure diagnosis and testing.
3. if the pressure test normal replace engine oil pressure sensor.

the oil pressure testing links to removing your oil filter and installing a mechanical gauge and looking for the min pressures above. the 6psi at 1000rpm stuff.

from the tests I've seen people do, it's always higher at the filter location than the back of the block sensor location with the same mechanical gauge anyways. but book says test with screw on oil filter adapter.


I honestly hate to see you dropping front diff, oil pan and pumps over something honestly a non issues. I've noticed a trend of everyone thinking everyone has a bad o ring, it rarely seems to be the fix all, and then you gotta go back in a 2nd time to install a high volume oil pump to get the needle up where you think it should be. when really an ls will out live all of us on 10psi hot idle oil pressure.


just my 2 cents.

thanks for the reply. wow, looking at those pressures you quoted, i would think those lifters would be banging out of the engine. I did replace the oil pressure sensor and inspected the connector and wiring. but still throwing that code. my Foxwell OBD tool doesn't have an oil pressure actual reading. so with the pressures you are quoting, other than that CEL coming on all the time, I don't have a problem.